Testing-machine



- H. L. SCOTT.

' TESTING MACHINE;

APPLICATION FILED JUNE 30. I919.

1920. 2 SHEETS-SHEET 1.

Patented Mar. 30

JVJJ

I lie/77A 860i? H. L. SCOTT.

TESTING MACHINE.

APPLICATION FILED JUNE 30, 1919.

71,335,402. I Patented Mar. 30, 1920.,

2 SHEETS-SHEET 2.

f/LW M. (5207? to be tested, and the UNITED STATES PATENT OFFICE.

HENRY L. SCOTTQOF PROVIDENCE'RHODE ISLAND, ASSIGNOR T0 HENRY L. SCOTT &

COMPANY, A COPARTNERSHIP COMPRISING- HENRY L.

OF PROVIDENCE, RHODE ISLAND.

SCOTT AND DAVID C. SCOTT,

TESTING-MACHINE.

Patented Mar. 30, 1920.

Application filed June 30, 1919. Serial No. 307,643.

To all whom it may concern:

Be it known that I, HENRY L. Scorr, a citizen of the United States, and resident of the city of Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Testing-Machines, of which the following is a specification. v

This invention relates to testing machines for applying tension to different materials object of this invention is to provide a mechanism of this character that is positive in its tensionapplying movement means also being provided whereby the action of the tensioning mechanism may be automaticallyreversed at a predetermined point in its stroke. a

A further object of the invention to provide means whereby the tension-operating mechanism may be caused to automatically stop at a predetermined point on its return stroke after having completed an operating stroke.

A still further object of the invention is the provision of means whereby the operating mechanism may be caused tofautomatically reverse its action at the end of both its operating and return strokes for the purpose of applying a so-called fatigue or. endurance test to rubber and the like.

I With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described, and particularly pointed out in the appended claims.

In the accompanying drawings:

Figure 1- is a side elevation partly in sectionillustrating the operating mechanism and also indicating the same as belted to be driven by an electric motor.

Fig. 2 is a side elevation showing the casing in section and illustrating the general arrangement of the driving and reversing mechanisms.

Fig. 3 is a top view illustrating spring snap reversing mechanism.

Fig.

the

4- 1s a sectional view illustrating the nut and worm gear through which the screw receives its traverse motion.

This invention relates more articularly to the mechanism by which tie traverse motion of the tension screw or rod is imparted in both directions, While the driving mechanism runs continuously in one direction.

It is found in practice most convenient to employ an electric motor for driving the mechanism but owing to the fact that it is diflicult from a practical standpoint to reverse this small, motor I have provided means whereby the operating mechanism itself may be automatically shifted to reverse the travel of the tension'screw. 7

To accomplish this reversing action in a simple and practical way I have provided a casing 10 having base flanges 11 which are adapted to be bolted to the upright 12. In this casing I have mounted the traversing tension rod or screw 13'which is arranged toeXtend through the casing and through the nut 14, see Fig. 4, mounted within the casing. This nut is adapted to be rotatedv through the worm gear 15 to impart an endwise motion to said screw, the latter being held from rotating by the key ,,15 -in the casing sliding in the keyway 16 in the screw. This gear 15 is provided with hubs 16 which are mounted between thrust bear-' ings 17 at either end thereof.

In order to transmit motion to this worm gear in opposite directions while the driver is running in the same direction, I have provided a frame having a hub 18 pivotally mounted on the upright shaft19, which frame is provided with a pair of radiating arms QO-arranged to straddle the tensionscrew rod 13. Each of these arms is pro vided with a pair of depending bearings 21 between which are mounted a worm screw and driving pinion 28, thepulley 26 receiving its motion from the electric motor 30' through pulley 29 and belt 31.

I have spacedthese worm screws 22 sufficiently apart so that when the frame is in the center, or non-operating position, neither of the screws will be in-engagement with the worm gear, at which time the mechanism may be run idle without imparting a traverse motion to the tension screw. The

two arms 20 on the frame are connected to- V the snap. shift arm 45.

pressed detent 43 engage notch 42 to retaln the shift bar gether at their'outer ends by a web 32 which web slides in'theguide 32 and is slotted'as at 33 to receive the upper end of arm 34 of the shift lever 35. This shift lever is mounted to oscillate on the pin 36 and is provided with a laterally extending arm 37 the end of which engages a notch 38 in the shift bar 39. This shift bar is mounted to slide endwise through the casing 10 and one of its edgesv is provided with three triangular notches 40, 41 and 42 respectively, which are adapted to be engaged by a spring whereby this detent will in up position, notch 41 to retain the bar in neutral position, and notch to retain the bar in down position, the front edge of this bar is'al'so notched at 44 to receive the end of The upper end of this shift bar 39 is provided with an operating handle 46.

The inner end of this snap shift arm" 45 is pivoted at47 in the frame 48 and its extremity is pivoted at 49 to the short arm 50 which is in turn pivoted at 51 also in the frame 48. A pair 'of springs 52 are connected at one end to a pin 53 inthe'shift arm 45 and at their opposite end to a' pin 54 in the short arm 50, whereby when this arm'45 is carried in either direction beyond a central line through both of the shift arms,"these springs serve to throw the arm 45 with a snap to engage and move the'shift I bar-39 as'presently described.

In order to operate this snap shift arm 45 at the'desired time I have mounted contact arms 55 and 56 on opposite ends of the tension screw 13, which arms are adapted to engage the adjustable contacting screws 57 in the shift, rod 58 and I have provided a pin 59 in the shift rod 58 to engage a slot 60in the shift arm 45 so that when the tension screw is moved on its downward stroke to exert a tension on the goods to be tested, the arm 55 is set in such a position that after the screw has traversed the desired distance, this arm 55 will engage the upper adjusting screw 57 on the rod 58 and move the rod downward together with the shift arm 45 until this arm snaps by the center and strikesthe lower edge 61 of the shift bar- 39, which movement throws the shift bar downward and acting'through the shift bell crank lever 35 swings the frame in which the worms are mounted, to move one worm rod upward until it causes the shift arm 45" to pass the horizontal position when this arm under action of its springs 52 snaps up- Ward against the edge 65 on the shift bar 39 to move the bar upward, In order to control the extent of this upward or reverse motion, I have inserted a stop pin. 62 in this rod which limits the middle notch 4.1 and; so cause the worms to be moved toneutral position and so arrest the movement of" the tension screw.

In order to again start the screw-feeding mechanism into action it is only necessary to raise the shift bar 39 by its handle 46 to its up position, which movement causes the bell crank lever '35 to move the left hand worm into engagement with the worm gearandstart the tension screw in a downward direction;

When it is desired to cause this mechanism to reverse its action at both ends of its stroke automatically it is only necessary to- I elastic material so as to'determine' just how many times the rubber may bestretched be fore it will break. a

When it is desired to apply the so-called set test to rubber strips it is only necessary to permit the tension screw to descend until it has exerted the proper tension upon the work when by operating the handle 46 by hand the shift bar 39 may be moved to neutral position, which will stop further motion to the tension screw until'set in motion by another manual action of this op crating handle. i V

On the upper end of the tension screw I have'shown the clamp head '63 which ongages the work 64 the rest of the usual tension indicating mechanism not being shown.

The foregoing description is directed solely toward the construction illustrated, but I desire it to be understood that I reserve the privilege of resorting" to all the mechanical changes to which the device is susceptible, the invention being defined and limited only by the terms of theappended claims.

I claim:

1. In a testing machine, a screw through which tension is applied for the test, a driving nut engaging said screw, means including a worm gear, and a pair of worms mounted to alternately engage and rotate said worm and nutin opposite directions to impart both an operating and a return movement to said screw.

2. In a testing machine, a screw through which tensionis applied for the test, a driving nut engaging said screw,.a worm-gear, a pair ofworms,means for m'ovingone worm of said pair to operate said gear nut and screw in one direction and moving the other worm to operate said gear nut and screw in the opposite direction.

3. In a testing machine, a screw through which tension is applied for the test, a driving nut engaging said screw, a worm gear arranged to drive said nut, a frame, a pair of worms mounted in said frame to engage opposite sides of said gear, and means for moving the opposite worms into engagement with said gear to drive said screw in opposite directions.

4. In a testing machine, a rod through which tension is applied for the test, a driving member acting on said rod, means for operating said member to actuate said rod, and means including a spring actuating snap shift mechanism for automatically reversing the direction of travel of said tension rod after an operating stroke.

5. In a testing machine, a screw through which tension is applied for the test, a driving nut engaging said screw, a worm gear arranged to drive said nut, a frame, a pair of Worms mounted in said frame to engage opposite sides of said geargand a snap shift mechanism controlled by the movement of said screw for moving the opposite worms alternately into engagement with said gear to move said screw endwise in opposite directions.

6. In a testing machine, a screw through which tension is applied for the test, a driv-' ing nut engaging said screw, means including a worm gear, a pair of worms mounted to alternately engage said Worm on opposite sides to rotate said nut in opposite directions, and means whereby said worms may be shifted automatically at opposite ends of the stroke of said screw to reverse the travel of said screw.

In testimony whereof I affix my signature.

HENRY L. SCOTT. 

